Showing papers by "Guo-Wei Wei published in 2002"
TL;DR: This paper presents a novel computational approach, the discrete singular convolution (DSC) algorithm, for analysing plate structures, and demonstrates that different methods of implementation for the present algorithm can be deduced from a single starting point.
Abstract: This paper presents a novel computational approach, the discrete singular convolution (DSC) algorithm, for analysing plate structures. The basic philosophy behind the DSC algorithm for the approximation of functions and their derivatives is studied. Approximations to the delta distribution are constructed as either bandlimited reproducing kernels or approximate reproducing kernels. Unified features of the DSC algorithm for solving differential equations are explored. It is demonstrated that different methods of implementation for the present algorithm, such as global, local, Galerkin, collocation, and finite difference, can be deduced from a single starting point. The use of the algorithm for the vibration analysis of plates with internal supports is discussed. Detailed formulation is given to the treatment of different plate boundary conditions, including simply supported, elastically supported and clamped edges. This work paves the way for applying the DSC approach in the following paper to plates with complex support conditions, which have not been fully addressed in the literature yet.
222 citations
TL;DR: In this article, a discrete singular convolution (DSC) algorithm is proposed for high frequency vibration analysis of plate structures. But, the proposed method is not suitable for the case of square plates with six distinct boundary conditions.
164 citations
TL;DR: In this paper, the authors introduced the discrete singular convolution (DSC) algorithm for the prediction and analysis of high-frequency vibration of structures, which can be applied to both a beam and two-span plates.
154 citations
TL;DR: In this article, a discrete singular convolution (DSC) approach is proposed for the analysis of rectangular plates with non-uniform and combined boundary conditions, and the validity of the DSC approach for plate vibration is tested by using a large number of numerical examples that have a combination of simply supported, clamped and transversely supported edges.
113 citations
TL;DR: In this article, a discrete singular convolution (DSC) algorithm was proposed for the vibration analysis of rectangular plates with internal supports and the results showed that the DSC algorithm exhibits controllable accuracy for plate analysis and shows excellent flexibility in handling complex geometries, boundary conditions and support conditions.
Abstract: Part 2 of this series of two papers presents the applications of the discrete singular convolution (DSC) algorithm. The main purpose of this paper is to explore the utility, test the accuracy and examine the convergence of the proposed approach for the vibration analysis of rectangular plates with internal supports. Both partial internal line supports and complex internal supports are considered for 21 square plates of various combinations of edge support conditions. The effects of different size, shape and topology of the internal supports and different boundary conditions on the vibration response of plates are investigated. The partial internal line supports may vary from a central point support to a full range of cross or diagonal line supports. Several closed-loop supports, such as ring, square and rhombus, and their combinations are studied for complex internal supports. Convergence and comparison studies are carried out to establish the correctness and accuracy of the DSC algorithm. The DSC results are compared with those in the available literature obtained by using other methods. Numerical results indicate that the DSC algorithm exhibits controllable accuracy for plate analysis and shows excellent flexibility in handling complex geometries, boundary conditions and support conditions. Copyright © 2002 John Wiley & Sons, Ltd.
103 citations
TL;DR: The discrete singular convolution (DSC) algorithm for edge detection is introduced and the performance of the proposed algorithm is compared with many other existing methods, such as the Sobel, Prewitt and Canny detectors.
101 citations
TL;DR: In this article, the problem of plate vibration under complex and irregular internal support conditions has been addressed by using discrete singular convolution (DSC) for solving this problem, which exhibits controllable accuracy for approximations and shows excellent flexibility in handling complex geometries, boundary conditions and internal support condition.
92 citations
TL;DR: This letter proposes a novel image edge detection algorithm based on the difference of two synchronizing spatially extended nonlinear dynamical systems, which shows some of the best image edges could be obtained by an appropriate balance between synchronization and desynchronization.
Abstract: This letter proposes a novel image edge detection algorithm based on the difference of two synchronizing spatially extended nonlinear dynamical systems. The time evolution of each system is identified as a low-pass filtering process, whereas the difference of two synchronizing states is identified as the result of high-pass filtering. Two systems are weakly coupled and allowed to take a common image as their initial value, but have different time scales in their dynamical motions. Results are compared with those of standard image processing schemes. Some of the best image edges could be obtained by an appropriate balance between synchronization and desynchronization.
82 citations
TL;DR: A control strategy for taming the wake turbulence behind a cylinder and it is shown that the base suction, wake formation length, absolute instability, and the Kármán vortex street are effectively controlled by the angular momentum injection.
Abstract: This Letter introduces a control strategy for taming the wake turbulence behind a cylinder. An angular momentum injection scheme is proposed to synchronize the vertical velocity field. We show that the base suction, wake formation length, absolute instability, and the Karman vortex street are effectively controlled by the angular momentum injection. A control equation is designed to implement the injection. The Navier-Stokes equations, along with the control equation, are solved. The occurrence of a new recirculation free zone is identified.
61 citations
TL;DR: Wavelet controlled dynamics is introduced as a new paradigm of dynamical control and it is found that by modifying a tiny fraction of the wavelet subspaces of a coupling matrix, it could dramatically enhance the transverse stability of the synchronous manifold of a chaotic system.
Abstract: Chaos is a class of ubiquitous phenomena and controlling chaos is of great interest and importance. In this Letter, we introduce wavelet controlled dynamics as a new paradigm of dynamical control. We find that by modifying a tiny fraction of the wavelet subspaces of a coupling matrix, we could dramatically enhance the transverse stability of the synchronous manifold of a chaotic system. Wavelet controlled Hopf bifurcation from chaos is observed. Our approach provides a robust strategy for controlling chaos and other dynamical systems in nature.
61 citations
TL;DR: The utility of the DSC?FSM approach is illustrated by two other benchmark problems, viz., the flow over a backward-facing step and the laminar flow past a square prism, which compare well with the numerical and experimental data available in the literature.
TL;DR: In this paper, a low-pass filter is introduced to intelligently eliminate the high frequency errors produced by conjugate high-pass filters for Burgers' equation with all possible values of Reynolds numbers.
TL;DR: In this paper, the authors explored the utility, tested the accuracy and examined the limitation of the discrete singular convolution (DSC) algorithm for solving partial differential equations (PDEs) The standard Fourier pseudospectral ( FPS) method is also implemented for a detailed comparison so that the performance of the DSC algorithm can be better evaluated.
TL;DR: In this paper, a discrete singular convolution (DSC) solver is developed for treating incompressible flows and three different two-dimensional benchmark problems, the Taylor problem, the driven cavity flow, and a periodic shear layer flow, are utilized to test the accuracy, to explore the reliability and to demonstrate the efficiency of the present approach.
Abstract: A discrete singular convolution (DSC) solver is developed for treating incompressible flows Three different two-dimensional benchmark problems, the Taylor problem, the driven cavity flow, and a periodic shear layer flow, are utilized to test the accuracy, to explore the reliability and to demonstrate the efficiency of the present approach Solution of extremely high accuracy is attained in the analytically solvable Taylor problem The results of treating the other problems are in excellent agreement with those in the literature Copyright © 2002 John Wiley & Sons, Ltd
TL;DR: In this paper, the Levy method is applied to investigate the vibration behavior of multi-span rectangular plates with at least two parallel simply supported edges, and the impact of the internal line supports on the vibration behaviour of the plates is investigated by varying both the number of internal lines and the line positions.
TL;DR: In this article, a conjugate low-pass filter is proposed to remove the accumulated numerical errors produced by a set of high-pass filters, which can be used for numerical computation involving shock waves.
Abstract: This paper introduces a new scheme for the numerical computation involving shock waves. The essence of the scheme is to adaptively implement a conjugate low-pass filter to effectively remove the accumulated numerical errors produced by a set of high-pass filters. The advantages of using such an adaptive algorithm are its controllable accuracy, relatively low cost and easy implementation. Numerical examples in one and two space dimensions are presented to illustrate the proposed scheme. Copyright © 2003 John Wiley & Sons, Ltd.
TL;DR: In this article, the discrete singular convolution (DSC) algorithm is applied to the Korteweg-de Vries (KdV) and modified KdV (mKDV) equations with a particular emphasis on a comparison with the Fourier pseudospectral (FPS) method.
TL;DR: In this article, two wavelet indices, multiscale accumulative density (MAD) and multi-scale accumulative change (MAC), are proposed for the characterization of the dynamics of the spatiotemporal patterns.
TL;DR: It is found that noise can induce the bifurcation and, more strikingly, it can enhance the temporal regularity of the wave pattern in the coupled system.
Abstract: We uncover a coherence resonance near the Hopf bifurcation from chaos in coupled chaotic oscillators. At the bifurcation, a nearly periodic rotating wave becomes stable as the state of synchronous chaos is destabilized. We find that noise can induce the bifurcation and, more strikingly, it can enhance the temporal regularity of the wave pattern in the coupled system. This resonant phenomenon is expected to be robust and physically observable.
TL;DR: In this paper, an anisotropic diffusion oscillation reduction (ADOR) scheme was proposed for image edge detection and numerical shock wave computations, based on the first principles of quantum mechanics.
TL;DR: The proposed controlled coupling process can locally minimize the smoothness and the fidelity of dynamical data and is demonstrated by chaos synchronization in Duffing oscillators and spatiotemporal synchronization of noisy nonlinear oscillators.
Abstract: This paper proposes an on-off coupling process for chaos synchronization and information processing. An in depth analysis for the net effect of a conventional coupling is performed. The stability of the process is studied. We show that the proposed controlled coupling process can locally minimize the smoothness and the fidelity of dynamical data. A digital filter expression for the on-off coupling process is derived and a connection is made to the Hanning filter. The utility and robustness of the proposed approach is demonstrated by chaos synchronization in Duffing oscillators, the spatiotemporal synchronization of noisy nonlinear oscillators, the estimation of the trend of a time series, and restoration of the contaminated solution of the nonlinear Schrodinger equation.
TL;DR: Situations are identified where the invariance of statistical averages breaks down as the noise amplitude increases through a critical level, and an algebraic scaling law is obtained which relates the change of the averages to the noise variation.
Abstract: We ask whether statistical averages in chaotic systems can be computed or measured reliably under the influence of noise. Situations are identified where the invariance of such averages breaks down as the noise amplitude increases through a critical level. An algebraic scaling law is obtained which relates the change of the averages to the noise variation. This breakdown of shadowability of statistical averages, as characterized by the algebraic scaling law, can be expected in both low- and high-dimensional chaotic systems.
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TL;DR: In this paper, a discrete singular convolution (DSC) filter is used to facilitate the Fourier pseudospectral method for the solution of hyperbolic conservation law systems.
Abstract: A class of high-order lowpass filters, the discrete singular convolution (DSC) filters, is utilized to facilitate the Fourier pseudospectral method for the solution of hyperbolic conservation law systems. The DSC filters are implemented directly in the Fourier domain (i.e., windowed Fourier pseudospectral method), while a physical domain algorithm is also given to enable the treatment of some special boundary conditions. By adjusting the effective wavenumber region of the DSC filter, the Gibbs oscillations can be removed effectively while the high resolution feature of the spectral method can be retained. The utility and effectiveness of the present approach is validated by extensive numerical experiments.